Hi, as a hunter and reviewer of bad webcomics, I'd like to suggest a some I've found for you wiki.

Hathor the Cow Goddess
What: The political\semi-authobiographical comic from militant breastfeeder and uber-hippie.
Why: The utter self-rightousness and in-your-face attitude of this self-proclaimed goddess will make even those who agree with the idea of breast feeding and anti-consumerism want her to shut-up. Her art barely makes it count as a comic.

Masters of the Art
What: The "wacky" adventures of a group of teens.
Why: It's a painful attempt at wacky with no substance, with little characterization, and no real character or story development.

Unicorn Jelly
What: A sci-fi story with fantasy elements that starts out as a simple story of a jelly monster and expands into n attempt at an epic adventure.
Why: The story tries too hard to be an epic, philosophical adventure; bad art, characters look alike, story really rushes ahead near the end, making everything really confusing. And the author is a total nut.

Questionable Content
What: Imagine a harem anime if it had emo 20-somethings.
Why: Too much talking and too many characters that come and go (especally in the earlier strips), not much happens, total muscial snobbiness at any music that isn't indy, and it has emos.

Wicked Powered
What: A hapless nerd discovers he's a manly hero in the future and has adventures with three hot girls with plenty of 80's retro toon references.
Why: It tries to be funny with it's 80's references but fails. The laser references feel like it's kissing up to it's former sponsor.

Candi
What: The life and loves of Candi and her college associates who share a boarding house.
Why: Horrid art (despite the fact the creator is an art school graduate), unlikeable cast, plots that drag on and go nowhere, characters personalities flip-flop when the plot demands it, the squirrel mafia storyline.

Least I Could Do
What: The adventures of a mysogynistic man named Rayne.
Why: This is a comic you either love or hate. Rayne is a major league mary-sue who is constantly rewarded for being a selfish, lazy, smug, mysogynist creep and sleeps with tons of attractive women and toss them aside. The author just can't bear to let Rayne take his lumps that he dumps storylines or some unrealistic twist appears and his naysayers are made to look bad. That and the humor sucks.

Nice Guy Comics
What: A self-proclaimed "nice guy", his friends, and the girl he loves.
Why: The so-called "Nice guy" is just a whiner who plays the poor little victim and the art sucks.

Sins
What: Various people come across a gauntlet that allows people to summon and use the powers of the seven deadly sins who are just run-of-the-mill demons who are kinda tired of their job.
Why: Horrid art and lazy character designs that the creator insists are part of her "simplistic" art style, plot jumps around so much that you're utterly dependant on the authors notes to get what's going on, only one character (Lust) has any personality and development, and there's no real plot.

Marry Me
What: A romantic comedy about a man who accidently marries a pop star his lesbian best friend loves.
Why: The romantic tension between the two love interests have little to no chemistry, the male lead has little personality (except that he's nice, a bit of a geek and listens well) and rarely reacts to anything, the characters don't really act like real people, the creator is an angry nutbag.

No Need for Bushido
What: A martial arts comedy
Why: Everything is either blantantly ripped off from another anime or is utterly ridiculous (like the time-traveling chick in a trenchcoat named Matrix). Cliche as hell with one of the most annouying females (Ina) to ever grace a webcomic.

Pibgorn
What: A geeky pianist is the beloved of a fairy and a succubus and they have adventures.
Why: The plots drag, the author tries too hard to be intellectual and fails, the hero is such a dullard that you wonder why these girls would want him, the creator is a first-rate douchebag.

Before I forget, I should warn you that anyone who goes after a Bobby Crosby comic is bound to earn that man's wrath. Same goes for anyone critising Least I Could Do because the fans will come an cry about how "Rayne is getting better" or how he's not a mary sue.

I know I'm late to this party, but I'm so glad to see that I'm not the only person on the internet who can't stand Questionable Content. I mean, sure his art's gotten better but really, how many people actually enjoy the comic rather than just reading it because they feel obligated to? Why is there not yet a review for Questionable Content?

I tried to read it, but around 700 pages in I sort of fell asleep.
I'm pretty sure it'd be a pretty straightforward review. Rambling on about indie bands,
sometimes he even makes up the bands just to have a band to talk about, almost every page ends with one of the many female girls making some sort of joke about farts.
And the robots that serve no purpose other than lol random. So… it's tenchi muyo only all of them are ryoko and instead of sex jokes we get punchlines involving a chick stinking up the bathroom.
High brow stuff here gaiz.

It kind of breaks my heart that it's not included in the reviews yet. I mean, it's one of the most overrated comics I've ever seen in my life. It just bothers the hell out of me that there are so many people out there who swear by it, and act like it's the holy grail of comics. It's insulting. Seriously, whenever I hear someone tell me how they idolize QC, I could vomit blood.